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Discussion Starter · #1 ·
I recently bought AA Headers, and for some reason when I start my car the RPM level in Idle drops below 500, and hops back up and sometimes dies. Sometimes it's fine, although sometimes it will sound like a tractor.. My shop said it's due to backpressure and it should ease up soon, or will clear up once I get my AA tune installed...

Any ideas on whats happening??

Thank you
 

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Discussion Starter · #6 ·
Far more possible than what your shop told you. About back pressure and tuning :eeps: :eeps: get a new shop! Also make sure your 02's wires aren't touching your headers anywhere. Do you have any check engine lights? Like misfires?
Service Engine Light is always on now, and was flashing this morning? And it backfires almost every time I start the car. And it keeps getting worse.
 

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Service Engine Light is always on now, and was flashing this morning? And it backfires almost every time I start the car. And it keeps getting worse.
My guess is they have either switched the pre cat bank 1 and 2 sensors round the wrong way OR your O2 sensor wires have burned up and are shorting.

Find someone with diagnostics software like INPA and monitor the voltages and resistance from the O2 sensors.

Good luck :thumbup:
 

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My guess is they have either switched the pre cat bank 1 and 2 sensors round the wrong way OR your O2 sensor wires have burned up and are shorting.

Find someone with diagnostics software like INPA and monitor the voltages and resistance from the O2 sensors.

Good luck :thumbup:
This need a DVOM/scanner that can give you real time voltage coming from your o2's at idle. If the voltage is constant something is wrong. I'm almost positive your 02's switched/wires burned up. GL man get under your dang car!
 

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A quick check. Just unhook all of your O2 sensors and see how the car runs. The car will run without the O2 sensors hooked up.

Then, get a wiring diagram (a Bentley Manual) and figure out what it bank 1 and what is bank 2. Once you get that figured out, then write on each plug, what it is.
 

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Discussion Starter · #13 ·
I bought 02 simulators from Bimmerbrakes, so when I bring it back could this possible fix the problem?

Thanks for all of the help guys
 

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Discussion Starter · #15 ·
Maybe next time I'll make the trip and bring it to IND Distributions in Chicago, IL.
 

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Discussion Starter · #16 ·
Yup, O2 sensors swapped. As well as an exhaust leak.... So there was a back pressure problem plus opposite placed o2 sensors. Thanks for all of the help guys!
 

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Yup, O2 sensors swapped. As well as an exhaust leak.... So there was a back pressure problem plus opposite placed o2 sensors. Thanks for all of the help guys!
Don't kid yourself, your exhaust leak had nothing to do with what was wrong with your car. It was your O2s being in the wrong place nothing else.
 

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Discussion Starter · #19 ·
Okay, so I got the o2 sensors fixed. I got the exhaust leaks fixed and new gaskets. When I was driving home it was idling rough again, and would get power though the gears? Now whats going on? Is this time for a tune or what?
 

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Did you clear the o2 codes after correcting their placement?
 
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